Endolymphatic hydrops in Meniere's disease detected by MRI after intratympanic administration of gadolinium: comparison with sudden deafness

A novel radiomics nomogram based on T2-sampling perfection with application-optimized contrasts using different flip-angle evolutions (SPACE) images for predicting cochlear and vestibular endolymphatic hydrops in Meniere's disease patients

OBJECTIVES

To construct and validate a radiomics nomogram based on T2-sampling perfection with application-optimized contrasts using different flip-angle evolutions (SPACE) images for predicting cochlear and vestibular endolymphatic hydrops (EH) in Meniere's disease patients.

METHODS

A total of 156 patients (312 affected ears) with bilateral definite Meniere's disease who underwent delayed enhancement MRI scans were enrolled in this study. All ears of the patients were divided into a training set (n = 218) and an internal validation set (n = 94). A radiomics nomogram was constructed from radiomics features extracted from the T2-SPACE images, and a radiomics score was calculated. Performance of the radiomics nomogram was assessed using receiver operating characteristics analysis.

RESULTS

Five features were selected for the construction of the cochlear radiomics nomogram, and seven features for the vestibular radiomics nomogram. The radiomics nomograms exhibited robust performance in differentiating between EH-positive and EH-negative statuses in both training and validation cohorts, with the area under the receiver operating characteristics curve values for cochlear and vestibular radiomic nomograms being 0.703 and 0.728 in the training set, and 0.718 and 0.701 in the validation set, respectively.

CONCLUSION

The novel radiomics nomograms based on T2-SPACE images were successfully constructed to predict cochlear and vestibular EH in Meniere's disease. The models showed a solid and superior performance and may play an important role in the EH prediction.

CLINICAL RELEVANCE STATEMENT

We constructed a novel radiomics nomogram, which can be a very useful tool for predicting cochlear and vestibular endolymphatic hydrops in Meniere's disease patients.

KEY POINTS

• This is the first T2-SPACE-based nomogram to predict cochlear and vestibular endolymphatic hydrops. • The nomogram is of great value to patients who are unable to undergo delayed enhancement MRI scans.

Delayed post gadolinium MRI descriptors for Meniere's disease: a systematic review and meta-analysis

OBJECTIVES

Delayed post-gadolinium magnetic resonance imaging (MRI) detects changes of endolymphatic hydrops (EH) within the inner ear in Meniere's disease (MD). A systematic review with meta-analysis was conducted to summarise the diagnostic performance of MRI descriptors across the range of MD clinical classifications.

MATERIALS AND METHODS

Case-controlled studies documenting the diagnostic performance of MRI descriptors in distinguishing MD ears from asymptomatic ears or ears with other audio-vestibular conditions were identified (MEDLINE, EMBASE, Web of Science, Scopus databases: updated 17/2/2022). Methodological quality was evaluated with Quality Assessment of Diagnostic Accuracy Studies version 2. Results were pooled using a bivariate random-effects model for evaluation of sensitivity, specificity and diagnostic odds ratio (DOR). Meta-regression evaluated sources of heterogeneity, and subgroup analysis for individual clinical classifications was performed.

RESULTS

The meta-analysis included 66 unique studies and 3073 ears with MD (mean age 40.2-67.2 years), evaluating 11 MRI descriptors. The combination of increased perilymphatic enhancement (PLE) and EH (3 studies, 122 MD ears) achieved the highest sensitivity (87% (95% CI: 79.92%)) whilst maintaining high specificity (91% (95% CI: 85.95%)). The diagnostic performance of "high grade cochlear EH" and "any EH" descriptors did not significantly differ between monosymptomatic cochlear MD and the latest reference standard for definite MD (p = 0.3; p = 0.09). Potential sources of bias were case-controlled design, unblinded observers and variable reference standard, whilst differing MRI techniques introduced heterogeneity.

CONCLUSIONS

The combination of increased PLE and EH optimised sensitivity and specificity for MD, whilst some MRI descriptors also performed well in diagnosing monosymptomatic cochlear MD.

KEY POINTS

• A meta-analysis of delayed post-gadolinium magnetic resonance imaging (MRI) for the diagnosis of Meniere's disease is reported for the first time and comprised 66 studies (3073 ears). • Increased enhancement of the perilymphatic space of the inner ear is shown to be a key MRI feature for the diagnosis of Meniere's disease. • MRI diagnosis of Meniere's disease can be usefully applied across a range of clinical classifications including patients with cochlear symptoms alone.

Advanced Magnetic Resonance Imaging Sheds Light on the Distinct Pathophysiology of Various Types of Acute Sensorineural Hearing Loss

OBJECTIVE

To compare the findings of magnetic resonance imaging (MRI) with advanced protocols in patients with various types of acute sensorineural hearing loss (ASNHL).

STUDY DESIGN

Retrospective case review.

SETTING

Tertiary referral center.

PATIENTS

Two hundred eighty-seven patients with ASNHL.

INTERVENTIONS

All patients underwent MRI scanning, including heavily T2-weighted three-dimensional fluid-attenuated inversion recovery before and 4 hours after the intravenous administration of gadolinium contrast medium (delayed 3D-FLAIR). A hybrid of the reversed image of the positive endolymph signal and the native image of the perilymph signal image was constructed to visualize the endolymphatic space.

RESULTS

The detection rates of abnormal MRI findings vary significantly among different types of ASNHL. A hyperintense signal on delayed 3D-FLAIR was observed in all patients with intralabyrinthine schwannoma or vestibular schwannoma and 20.5% of patients with idiopathic sudden sensorineural hearing loss (ISSNHL) but was rarely observed in definite Ménière's disease (MD, 2.6%). In contrast, endolymphatic hydrops (EH) was frequently observed in patients with definite MD (79.5%) but was observed much less frequently in patients with ISSNHL (11.0%). In patients with cochlear MD and ALHL, detection rates of cochlear EH were similar to those with definite MD, whereas detection rates of vestibular EH were significantly lower than in patients with definite MD.

CONCLUSIONS

The significantly different detection rates of abnormal MRI findings among various types of ASNHL shed light on the distinct pathophysiology of each disorder. A diagnosis based on MRI findings with advanced protocols may help select treatment strategies and provide prognostic information for patients.

Visualization of Endolymphatic Hydrops in Patients With Unilateral Idiopathic Sudden Sensorineural Hearing Loss With Four Types According to Chinese Criterion

Objective: The aim of this study is to evaluate the possible value of endolymphatic hydrops (EH) in patients with unilateral idiopathic sudden sensorineural hearing loss (UISSNHL) with four types according to audiometry.

Methods: Seventy-two patients (40 men and 32 women; age range, 28–78 years; mean age: 50.0 ± 12.9 years) with UISSNHL were admitted retrospectively into this study. Based on the pure tone audiometry before treatment, the hearing loss of all these patients were categorized into four types: low-frequency group (LF-G), high-frequency group (HF-G), flat group (F-G), and total deafness group (TD-G). The average time from symptom onset to the first examination was 6.9 ± 4.4 days (1–20 days). 3D-FLAIR MRI was performed 24 h after intratympanic injection of gadolinium (Gd) within 1 week after the UISSNHL onset. The incidence of EH in the affected ears based on four types of hearing loss were analyzed using the Chi-square test, and the possible relationship with vertigo and prognosis were also assessed.

Results: Eleven of 21 patients (52.4%) in LF-G had the highest EH-positive rate, followed by 18.2% in HF-G, 11.8% in F-G, and 17.4% in TD-G. The significant difference was found in the four groups (P = 0.018). The EH rate of LF-G was statistically significantly higher than that of F-G and TD-G (P = 0.009, P =0.014), respectively. After being valued by the volume-referencing grading system (VR scores), the EH level was represented by the sum scores of EH. In LF-G, no statistically significant difference was found in the prognosis of ISSNHL patients between with the EH group and the no EH group (P = 0.586). The symptom “vertigo” did not correlate with EH and prognosis.

Conclusions: EH was observed in UISSNHL patients by 3D-FLAIR MRI. EH may be responsible for the pathology of LF-G but not related to prognosis. It might be meaningless to assess EH in other hearing loss types, which might be more related to the blood-labyrinth dysfunction.

Endolymphatic Hydrops in Fluctuating Hearing Loss and Recurrent Vertigo

Background: Endolymphatic hydrops (EH) is the histopathological hallmark of Ménière's disease (MD) and has been found by in vivo magnetic resonance imaging (MRI) in patients with several inner ear syndromes without definite MD criteria. The incidence and relevance of this finding is under debate.

Purpose: The purpose of the study is to evaluate the prevalence and characteristics of EH and audiovestibular test results in groups of patients with fluctuating audiovestibular symptoms not fulfilling the actual criteria for definite MD and compare them with a similar group of patients with definite MD and a group of patients with recent idiopathic sudden neurosensory hearing loss (ISSNHL).

Material and Methods: 170 patients were included, 83 with definite MD, 38 with fluctuating sensorineural hearing loss, 34 with recurrent vertigo, and 15 with ISSNHL. The clinical variables, audiovestibular tests, and EH were evaluated and compared. Logistic proportional hazard models were used to obtain the odds ratio for hydrops development, including a multivariable adjusted model for potential confounders.

Results: No statistical differences between groups were found regarding disease duration, episodes, Tumarkin spells, migraine, vascular risk factors, or vestibular tests; only hearing loss showed differences. Regarding EH, we found significant differences between groups, with odds ratio (OR) for EH presence in definite MD group vs. all other patients of 11.43 (4.5–29.02; p < 0.001). If the ISSNHL group was used as reference, OR was 55.2 (11.9–253.9; p < 0.001) for the definite MD group, 9.9 (2.1–38.9; p = 0.003) for the recurrent vertigo group, and 5.1 (1.2–21.7; p = 0.03) for the group with fluctuating sensorineural hearing loss.

Conclusion: The percentage of patients with EH varies between groups. It is minimal in the ISSNHL group and increases in groups with increasing fluctuating audiovestibular symptoms, with a rate of severe EH similar to the known rate of progression to definite MD in those groups, suggesting that presence of EH by MRI could be related to the risk of progression to definite MD. Thus, EH imaging in these patients is recommended.

Clinical Practice Guideline: Ménière's Disease

OBJECTIVE

Ménière's disease (MD) is a clinical condition defined by spontaneous vertigo attacks (each lasting 20 minutes to 12 hours) with documented low- to midfrequency sensorineural hearing loss in the affected ear before, during, or after one of the episodes of vertigo. It also presents with fluctuating aural symptoms (hearing loss, tinnitus, or ear fullness) in the affected ear. The underlying etiology of MD is not completely clear, yet it has been associated with inner ear fluid (endolymph) volume increases, culminating in episodic ear symptoms (vertigo, fluctuating hearing loss, tinnitus, and aural fullness). Physical examination findings are often unremarkable, and audiometric testing may or may not show low- to midfrequency sensorineural hearing loss. Conventional imaging, if performed, is also typically normal. The goals of MD treatment are to prevent or reduce vertigo severity and frequency; relieve or prevent hearing loss, tinnitus, and aural fullness; and improve quality of life. Treatment approaches to MD are many and typically include modifications of lifestyle factors (eg, diet) and medical, surgical, or a combination of therapies.

PURPOSE

The primary purpose of this clinical practice guideline is to improve the quality of the diagnostic workup and treatment outcomes of MD. To achieve this purpose, the goals of this guideline are to use the best available published scientific and/or clinical evidence to enhance diagnostic accuracy and appropriate therapeutic interventions (medical and surgical) while reducing unindicated diagnostic testing and/or imaging.

Magnetic resonance imaging of endolymphatic space in patients with sensorineural hearing loss: comparison between fluctuating and idiopathic sudden sensorineural hearing loss

Background: Recently, 3-Tesla magnetic resonance imaging (MRI) after an intravenous gadolinium injection has been used to describe the endolymphatic space (ELS).Objectives: This study described the histopathological differences between idiopathic sudden sensorineural hearing loss (ISSNHL) and fluctuating sensorineural hearing loss (FSNHL) by examining the ELS. Additionally, the relationship between the affected cochlear and vestibular ELS/total fluid space (TFS) volume ratio and the duration from the onset to MRI in patients with FSNHL were evaluated.Material and methods: This study included 205 individuals without vertigo: 47 controls, 94 with ISSNHL, and 64 with FSNHL. The TFS and ELS volumes were measured and the ELS/TFS volume ratios (%) were evaluated.Results: The cochlear and vestibular ELS/TFS volume ratios of the affected ear in patients with FSNHL were significantly higher than that in those with ISSNHL. There was no correlation between the duration from FSNHL onset to the MRI scan in the affected cochlea and vestibule.Conclusion and significance: There were differences in the form of hearing fluctuation and the extended ELS volume between ISSNHL and FSNHL. ISSNHL cases with severe ELS extension were likely to change to FSNHL.

Value of Endolymphatic Hydrops and Perilymph Signal Intensity in Suspected Ménière Disease

BACKGROUND AND PURPOSE

Ménière disease is characterized by endolymphatic hydrops, whereas perilymphatic enhancement on MR imaging has been suggested to be of additional value in diagnosing Ménière disease. This study evaluates the presence of endolymphatic hydrops and perilymphatic enhancement in patients with Ménière disease and with other vertigo-associated inner ear pathology.

MATERIALS AND METHODS

A 3D-FLAIR sequence 4 hours after intravenous gadolinium injection was performed to visualize the endolymph and perilymph in 220 patients suspected of having Ménière disease. Patients' ears were retrospectively categorized as having Ménière disease (probable or definite) or other vertigo-associated inner ear pathology not attributable to Ménière disease. Endolymphatic hydrops was evaluated using a visual classification system, and perilymphatic enhancement was scored both visually and quantitatively.

RESULTS

Endolymphatic hydrops was present in 137 (91.9%) of the definite Ménière disease ears and in 9 (7.0%) of the ears with other vertigo-associated inner ear pathology (P < .001). The combination of endolymphatic hydrops and visually increased perilymphatic enhancement was present in 122 (81.9%) definite Ménière disease ears compared with 4 (3.1%) ears with other vertigo-associated inner ear pathology (P < .001). This combination increases the positive predictive value from 0.94 for endolymphatic hydrops and 0.91 for perilymphatic enhancement to 0.97. The addition of measured perilymphatic enhancement leads to a moderate decrease in sensitivity from 0.92 for endolymphatic hydrops to 0.86.

CONCLUSIONS

The combination of perilymphatic enhancement and endolymphatic hydrops in patients suspected of having Ménière disease increases the positive predictive value in the diagnosis of definite Ménière disease.

Magnetic resonance-based volumetric measurement of the endolymphatic space in patients with Meniere's disease and other endolymphatic hydrops-related diseases

OBJECTIVE

To employ magnetic resonance imaging (MRI) to measure the volume of the inner ear endolymphatic space (ELS) in patients with acute low-tone sensorineural hearing loss (ALHL), sudden deafness (SD), cochlear Meniere's disease (cMD), and unilateral MD (uMD) compared with control subjects (CS) with chronic rhinosinusitis.

METHODS

Forty-one patients with ALHL, 82 with SD, 48 with cMD, 72 with uMD, and 47 CS participated in the study. With the exception of all uMD patients, none of the subjects had vertigo. Images of the inner ear fluid space, positive perilymph signal, and positive endolymph signal were acquired using a 3-T MRI scanner. Three-dimensional images were reconstructed semi-automatically by using anatomical and tissue information to fuse the inner ear fluid space images and the ELS images.

RESULTS

The cochlear ELS/total fluid space (TFS) volume ratio was 10.2±6.7% (mean±standard deviation) in the CS group, 12.1±5.7% in ALHL patients, 15.2±8.7% in SD patients, 18.1±8.2% in cMD patients, and 21.9±16.4% in uMD patients. The vestibular ELS/TFS volume ratio was 17.7±10.2% in the CS group, 18.9±8.3% in ALHL patients, 19.9±11.3% in SD patients, 22.5±13.7% in cMD patients, and 35.7±24.1% in uMD patients. The cochlear ELS/TFS volume ratio in patients with uMD was similar to that in the cMD group and significantly higher than that in the CS, ALHL, and SD groups (CS=ALHL<SD<cMD=uMD: p<0.05 for CS vs. SD and p<0.01 for CS vs. cMD). The vestibular ELS/TFS volume ratio in patients with uMD was significantly higher than that in the CS and all other patient groups (CS=ALHL=SD=cMD<uMD: p<0.01 for uMD vs. all other groups).

CONCLUSION

The cochlear ELS volume of patients with MD and other endolymphatic hydrops-related diseases differed from that of CS. Our results suggest that ALHL may not be caused by endolymphatic hydrops. We confirmed the presence of extended ELS in patients with SD.

Menière and Friends: Imaging and Classification of Hydropic Ear Disease

BACKGROUND

Over 75 years ago, endolymphatic hydrops was discovered as the pathologic correlate of Menière's disease. However, this pathologic finding could be ascertained only in postmortem histologic studies. Due to this diagnostic dilemma and the variable manifestation of the various audiovestibular symptoms, diagnostic classification systems based on clinical findings have been used hitherto.

METHODS

A review of the literature of magnetic resonance (MR) imaging of hydropic ear disease.

RESULTS

Recent developments of high resolution MR imaging of the inner ear have now enabled us to visualize in vivo endolymphatic hydrops in patients with suspected Menière's disease. The existing knowledge from temporal bone histologic studies and from the emerging evidence on imaging based evaluation of patients with suspected Menière's disease indicate that endolymphatic hydrops not only is responsible for the full-blown clinical triad of simultaneous attacks of auditory and vestibular dysfunction, but also for other clinical presentations such as "vestibular" and "cochlear Menière's disease."

CONCLUSION

As a consequence, we propose the term "Hydropic Ear Disease" as a new terminology which is based on symptomatic and imaging characteristics of these clinical entities to clarify and simplify their diagnostic classification.

What is Menière's disease? A contemporary re-evaluation of endolymphatic hydrops

Menière's disease is a chronic condition with a prevalence of 200-500 per 100,000 and characterized by episodic attacks of vertigo, fluctuating hearing loss, tinnitus, aural pressure and a progressive loss of audiovestibular functions. Over 150 years ago, Prosper Menière was the first to recognize the inner ear as the site of lesion for this clinical syndrome. Over 75 years ago, endolymphatic hydrops was discovered as the pathologic correlate of Menière's disease. However, this pathologic finding could be ascertained only in post-mortem histologic studies. Due to this diagnostic dilemma and the variable manifestation of the various audiovestibular symptoms, diagnostic classification systems based on clinical findings have been repeatedly modified and have not been uniformly used in scientific publications on Menière's disease. Furthermore, the higher level measures of impact on quality of life such as vitality and social participation have been neglected hitherto. Recent developments of high-resolution MR imaging of the inner ear have now enabled us to visualize in vivo endolymphatic hydrops in patients with suspected Menière's disease. In this review, we summarize the existing knowledge from temporal bone histologic studies and from the emerging evidence on imaging-based evaluation of patients with suspected Menière's disease. These indicate that endolymphatic hydrops is responsible not only for the full-blown clinical triad of simultaneous attacks of auditory and vestibular dysfunction, but also for other clinical presentations such as "vestibular" and "cochlear Menière's disease". As a consequence, we propose a new terminology which is based on symptomatic and imaging characteristics of these clinical entities to clarify and simplify their diagnostic classification.

Visualization of endolymphatic hydrops with MR imaging in patients with Ménière's disease and related pathologies: current status of its methods and clinical significance

Ménière's disease is an inner ear disorder characterized by vertigo attacks, fluctuating low-frequency hearing loss, ear fullness, and tinnitus. Endolymphatic hydrops has long been thought to be the pathological basis for Ménière's disease. Some patients have inner ear symptoms that do not match the diagnostic guidelines for Ménière's disease, and these are also thought to be related to endolymphatic hydrops. The diagnosis of endolymphatic hydrops is usually made based on clinical symptoms with some assistance from otological functional tests. Recently, the objective diagnosis of endolymphatic hydrops by MR imaging has become possible and many research results have been reported regarding the imaging methods, evaluation methods, the correlation between imaging results and functional otological tests and the correlation between imaging findings and clinical symptoms. In this article we summarize the development of current imaging methods, evaluation techniques and clinical reports based on a review of the literature. We also attempt to characterize the current significance and future directions of MR imaging of endolymphatic hydrops.

Changes in endolymphatic hydrops after sac surgery examined by Gd-enhanced MRI

CONCLUSION

Endolymphatic hydrops could be a reversible inner ear pathological condition. After sac surgery, hydrops was reduced and symptoms went into remission in some cases, although vertigo suppression was not always a result of the reduced hydrops.

OBJECTIVE

To examine the changes in endolymphatic hydrops detected by gadolinium (Gd) contrast-enhanced magnetic resonance imaging (MRI) before and 6 months after endolymphatic sac surgery in patients with unilateral Ménière's disease.

METHODS

Fluid-attenuated inversion recovery MRI was obtained 4 h after intravenous administration or 24 h after intratympanic administration of Gd contrast medium. An enlarged negative stain corresponding to the cochlear duct and endolymphatic space of the vestibule was assessed as hydrops.

RESULTS

Of seven patients with hydrops confirmed by MRI before surgery, both cochlear and vestibular hydrops became negative in two, cochlear hydrops became negative in one, both hydrops were present, but reduced, in one, and there was no change in three patients. The number of vertigo spells was reduced in all cases at 6-12 months after surgery. As for the three cases of negative hydrops, vertigo was completely suppressed. In two cases in which hearing level improved, hydrops became negative after surgery.

Effect of standard-dose Betahistine on endolymphatic hydrops: an MRI pilot study

This study aimed to assess whether standard-dose Betahistine (48 mg daily) exerts an effect upon the degree of endolymphatic hydrops in patients with Menière's disease using a retrospective case series in the setting of a tertiary neurotology referral centre. In six patients with definite unilateral Menière's disease, the degree of cochlear and vestibular endolymphatic hydrops was assessed before and after treatment with a standard dose of Betahistine (48 mg daily), using high-resolution 3 T MR imaging after intratympanic contrast medium application. The treatment duration was 3-7 months (mean 5 months), and the patients were followed-up for 6-29 months (mean 11 months). In the study cohort, the standard dose of Betahistine did not have an MR morphologically measurable beneficial effect on the degree of endolymphatic hydrops. The results indicated no effect of standard-dose Betahistine on endolymphatic hydrops found on high-resolution MR imaging. Possible explanations are: (1) insufficient dosage or duration of treatment with betahistine, (2) insufficient resolution of the MR imaging technique, and (3) insufficient length of follow-up. Further studies addressing these issues are warranted.

Comparison of contrast effect on the cochlear perilymph after intratympanic and intravenous gadolinium injection

BACKGROUND AND PURPOSE

3D-FLAIR imaging 24 hours after intratympanic gadolinium injection (IT-method) or 4 hours after IV injection (IV-method) has been used to visualize the endolymphatic hydrops in Ménière disease. The purpose of this study was to compare the degree of perilymph enhancement with the 2 methods and the perilymph contrast-effect difference with the IV-method in both sides in patients with unilateral Ménière disease.

MATERIALS AND METHODS

Sixty-one patients with Ménière disease or sudden SNHL were included in this study. Thirty-nine patients who underwent the unilateral IT-method (Gd-DTPA was diluted 8-fold with saline) and 22 patients who underwent the IV-method (a double-dose of Gd-HP-DO3A; 0.4 mL/kg body weight [ie, 0.2 mmol/kg body weight]) at 3T were analyzed retrospectively. Regions of interest of the cochlear perilymph and the medulla oblongata were determined on each image, and the signal-intensity ratio between the 2 (CM ratio) was subsequently evaluated. The differences in the CM ratio between the 2 methods (Student t test) and the IV-method CM ratio between the affected and unaffected sides in patients with unilateral Ménière disease (paired t test) were evaluated.

RESULTS

The IT-method CM ratio (2.98 ± 1.15, n = 39) was higher than the IV-method CM ratio (1.61 ± 0.60, n = 44; P < .001). In patients with unilateral Ménière disease who underwent the IV-method (n = 9), the CM ratio of the affected side (1.86 ± 0.74) was higher than that of the unaffected side (1.29 ± 0.31, P < .05).

CONCLUSIONS

In general, the IT-method provides higher perilymph enhancement than the IV-method. In the patients with unilateral Ménière disease who underwent the IV-method, the affected side had a higher contrast effect.

Contrast enhancement of the inner ear in magnetic resonance images taken at 10 minutes or 4 hours after intravenous gadolinium injection

CONCLUSION

Contrast enhancement of the inner ear by three-dimensional fluid-attenuated inversion recovery magnetic resonance imaging (3D-FLAIR MRI) taken 4 h after intravenous gadolinium (Gd) injection was better than when taken at 10 min. Using heavily T2-weighted 3D-FLAIR MRI, visualization of endolymphatic hydrops (EH) was possible in the vestibule and the cochlea after a standard intravenous dose of Gd.

OBJECTIVES

To define a suitable time point for imaging Gd uptake in the inner ear acquired with heavily T2-weighted 3D-FLAIR MRI after standard intravenous Gd administration.

METHODS

Using a 3 Tesla MRI unit, heavily T2-weighted 3D-FLAIR MRI images were taken twice at approximately 10 min (conventional timing) and 4 h after intravenous gadodiamide (0.1 mmol/kg) injection in 10 patients with inner ear diseases including Ménière's disease.

RESULTS

The 4 h delay increased Gd enhancement of the 3D-FLAIR MRI images of the perilymphatic space in both symptomatic and asymptomatic ears. The increase in Gd enhancement was greater in symptomatic than in asymptomatic ears. Using this heavily T2-weighted 3D-FLAIR technique, EH was observed in both the cochlea and vestibule in images taken 4 h after the intravenous Gd injection.